anatomy exam part 2

There are 3 subgroups (state the subgroups) that make up the superficial muscles and help with maintaining posture. These subgroups are known collectively as the erector spinae

3 subgroups iliocostalis longissimus spinalis Don't forget the quadratus lumborum; it connects from the twelfth rib to the iliac crest and also extends the spine

Most parts of the sarcomere shorten during contraction, but what part of the sarcomere stays the same size during contraction?

A Band

What is the I band of the sarcomere?

Actin filaments, Z discs, and connectin - but no overlap with thick filaments.

Of the three systems that make energy for muscle cells, which one uses oxygen and makes the most ATP?

Aerobic cellular respiration

levator ani

+ coccygeus = pelvic diaphragm consists of iliococcygeus and pubococcygeus inferior to coccygeus support abdominal organs inferiorly, forming muscular wall that prevents organs from slipping through opening in pelvis

coccygeus

+ levator ani = pelvic diaphragm superior to levator ani support abdominal organs inferiorly, forming muscular wall that prevents organs from slipping through opening in pelvis

Put the steps of cross-bridge cycling in the order they occur, starting with formation of cross-bridges between myosin and actin.

Cross-bridge formation (myosin binds to actin) Myosin head pulls and slides actin filament, myosin releases ADP and Pi Myosin head binds ATP and releases from actin. Myosin head resets as it breaks down ATP into ADP and Pi.

What is the 'neuro' part of the neuromuscular junction?

It's the axon terminal of a motor neuron that contacts the muscle cell.

Pterygoids

Origin: Pterygoid plate, greater wing of sphenoid (L), maxilla (M) .Insertion: Mandible.Action: Moves jaw from side to side, protracts, "excursions"

temporalis

Origin: Temporal fossa. Insertion: Mandible. Action: Closes jaw, retracts mandible.

Masseter

Origin: Zygomatic arch. Insertion: lateral side of mandible. Action: Primer mover of jaw-moving muscle group; elevates and protracts jaw.

Thoracic muscles and breathing

Scalenes, intercostals, and diaphragm. Understand that these muscles are synergists; be able to state the prime mover of the group.

Why is skeletal muscle rich in blood vessels and innervation?

Skeletal muscles need to bring in a lot of oxygen and nutrients and quickly remove wastes to function properly. Nerves allow us to control contraction consciously.

What does the sarcoplasmic reticulum do in muscle cells?

Stores calcium and releases it when the action potential travels into the T tubule.

Two sets of trunk muscles are responsible for moving the vertebral column and keeping us upright.

The deep group (intertransversarii, rotatores, multifidus, and interspinales muscles) connect from one vertebrae to the next, and allow the spine to extend, rotate, land laterally flex. Deep group: from vertebra to vertebra - Superficial group extend from vertebrae to ribs

The muscle fibers arranged in the orbicularis oculi have a circular arrangement -- what does this mean?

They are arranged in a ring around an opening.

What do you know to be true for "slow oxidative fibers"?

They use aerobic respiration to make ATP, are a darker red color because they have myoglobin, and usually have slower contractions than fast fibers.

The occipitofrontalis muscle has its origin on the occipital bone and inserts into the skin of the eyebrows and nose. What would you expect its action to be?

To wrinkle the forehead, as it moves the scalp and eyebrows.

lateral compartment muscles

abducts thigh

medial compartment muscles

adduct thigh

The muscle whose action is opposite that to the action of the agonist is the _____.

antagonist

tibialis anterior

anterior compartment dorsiflex, invert

extensor digitorum longus

anterior compartment extend toes

rectus abdominis

anterior most; deep to rectus sheath muscle more medial

Where is the rectus abdominus located?

anterior-most part of the abdominal wall, under the rectus sheath.

The erector spinae muscles (spinalis, longissimus, and iliocostalis)

are the superficial trunk muscles that maintain posture and keep the spine erect.

dorsiflex

bend foot toward upper surface (point toes up)

mastication

chewing. Involves elevation/depression of the mandible and excursion to grind the teeth together, TMJ• Act with the muscles of hyoid in movement of the mandible • Muscles of the cheek and tongue aid mastication by pushing the food under the teeth• Masseter, temporalis, lateral and medial pterygoids

pelvic diaphragm

coccygeus+levator ani support abdominal organs inferiorly, forming muscular wall that prevents organs from slipping through opening in pelvis

internal obliques

deep to external oblique and rectus abdominis, between external oblique and transversus more lateral when unilaterally contracted, laterally flex vertebral column rotates vertebral column to opposite side of contracting muscles

transversus abdominis

deepest abdominal muscle more lateral when unilaterally contracted, laterally flex vertebral column rotates vertebral column to opposite side of contracting muscles

Which one of the following muscles is most likely to be involved in a frown?

depressor anguli oris

The following muscles are all used in breathing. Which one is the prime mover?

diaphragm

prime mover

diaphragm

Intrinsic muscles:

entirely within the tongue and allow change in shape•

lateral compartment

evertors with some plantar flexion

quadriceps

extend

anterior compartment muscles

extend knee/flex thigh

As part of the posterior compartment muscles of the thigh, the hamstrings

extend the hip

triceps brachii

extends elbow and shoulder, adducts arm

general actions of posterior group

extension of wrist, hand, fingers

gracilis

flex

hamstrings

flex

posterior compartment

flex

sartorius

flex

posterior compartment muscles

flex knee or extend thigh

Generally speaking, the anterior arm muscles (ie, biceps brachii)

flex the elbow

brachialis

flexes elbow

brachioradialis

flexes elbow

biceps brachii

flexes shoulder and elbow, supinates forearm and hand

general actions of anterior group of muscles in forearm

flexion, abduction adduction little pronation

plantar flex

foot moves downward away from body (point toes down)

Which set of muscles moves the tongue?

genioglossus, palatoglossus, styloglossus

retinacula of forearm

help hold tendons close to bone

Extrinsic muscles:

insert in tongue and allow change in shape and movement

The _____ is the more mobile end of the muscle.

insertion

anterior compartment

invertors

rotation and abduction

lateral and posterior groups

fibularis longus

lateral compartment evertors with some plantar flexion

gastrocnemius

lateral compartment evertors with some plantar flexion

prime mover

masseter

Due to its size and locations of its origin and insertion, the trapezius muscle has multiple actions. One of those actions is

moves/stabilizes the scapula.

flexion

musclmuscles deep within neck along anterior/lateral margins of vertebral bodies

What protein will you find in thick filaments?

myosin

tensor fasciae latae

origin - anterior superior iliac spine insertion - lateral condole of tibia abducts, medial rotation

hyoglossus

origin - hyoid bone depresses/retract tongue

iliopsoas

origin - iliac fossa of pelvis insertion - lesser trochanter of femur adduct and flex

gluteus maximus

origin - ilium and sacrum insertion - femur and iliotibial tract extend, rotate

sartorius

origin - immediately below anterior superior iliac spine insertion - upper medial of shaft of tibia flex thigh and flex knee

palatoglossus

origin - inferior surface of palatine aponeurosis lifts back of tongue

biceps femoris (hamstring)

origin - is hail tuberosity of os coxa insertion - lateral side of head of fibula extend thigh, move knee

semitendinosus (hamstring)

origin - ischial tuberosity insertion - proximal end of tibia extend thigh, move knee

genioglossus

origin - mandible sticks tongue out

pectineus

origin - pectineal line of pubis insertion - pectineal line of femur adduct and flex

adductor magnus

origin - pubis insertion - lines aspera and adductor tubercle of femur extends and laterally rotates

gracilis

origin - pubis insertion - tibia adduct and flex

styloglossus

origin - styloid process of temporal bone retraction/elevation of tongue

semimembranosus (hamstring)

origin - superior lateral quadran of ischial tuberosity insertion - posterior surface of medial tibial condyle extend thigh, move knee

sternocleidomastoid

pair lateral neck laterally flex/rotate head if both contract, flex neck

Muscles that move the arm and rotator cuff:

pectoralis major latissimus dorsi deltoid(***) subscapularis infraspinatus supraspinatus teres minor

Muscles in the posterior compartment of the leg, like the gastrocnemius muscle,

plantar flex (push down) the foot.

semispinalis capitis

posterior neck extends neck

trapezius

posterior neck extends neck (somewhat), mostly move scapula, supports arm

splenius capitis

posterior neck (superficial to semispinalis capitis) extends, rotates, laterally flexes neck

extension

posterior neck muscles attach to occipital bone

The masseter is the prime mover of the muscles involved in chewing (mastication). It

pulls the jaw up and forward.

invert

soles of feet face inward side (medially)

evert

soles of feet face outward side (laterally)

soleus

superficial posterior compartment flex

external obliques

superficial to rectus abdominis more lateral when unilaterally contracted, laterally flex vertebral column rotates vertebral column to opposite side of contracting muscles

The sternocleidomastoid has its origins on the manubrium and clavicle and inserts onto the mastoid process. When both contract equally,

the neck flexes.

Muscles that act on the scapula

trapezius levator scapulae rhomboid major and rhomboid minor pectoralis minor serratus anterior